Matter: Its Three Phases, Properties and Characteristics
Matter is anything that occupies space that has mass and weight. In physics, it's a general term applied to anything that has the property of occupying space and the attributes of gravity and inertia. In classical physics, matter and energy were thought to be two individual concepts that place at the root of all physical phenomena. There are typical characteristics of three phases of matter:
Air moves and surrounds us. Water streams and looks wet. Rocks are callous and have a rigorous shape. These are the state and phases of matter. But before we compare each phase, we need to know the differences between “state and phases” of matter.
A phase refers to a physically unique and mechanically separable part of the system while a state refers to a fixed condition defined by a set of variables – pressure, temperature and concentration of solution.
A substance has an enormous number of possible states. If we change one variable such as temperature from 0ᵒC to 47ᵒC it will probably change its state.
Comparison of three Phases of Matter
Air in balloons
Definite (has its own shape, independent of its container)
Indefinite (takes the shape of the container but may not fill up all of it)
Indefinite (takes the shape of the container and occupies the whole container)
Indefinite (fills up the entire container)
To understand better the differences in the properties of gases, liquid and solid it would be very helpful to have a model of each phase. This model will provide a clearer visualization of what we can see.
Each model picture contains particles – it can be atoms, molecules or group of atoms. For some elements, a molecule may contain a single atom or a combination of two or more atoms.
- A single helium atom contains all the properties of helium thus, helium is considered a monoatomic molecules.
- Two oxygen atoms chemically combined ordinarily makes all the properties of oxygen thus, it is considered a diatomic molecules.
Definition of terms:
- Monoatomic molecules – contains a single atom
- Diatomic molecules – contains chemically combined atoms
What is the 4th phase of matter?
The three phases varies in the degree of orientation of molecules. With some exception, solid molecules are close to each other while gas molecules are far and are much separated from one another than liquid.
In a solid, the force that holds particles together to keep molecules intact is called forces of attraction between molecules. These intermolecular forces of attraction are stronger as particles move closer to each other.
- When we put several magnets near to each other, magnets pulls each other causing each magnet to draw closer to each other.
Molecules have kinetic energy which allows them to move simultaneously. In this way, three (3) forces are created:
- Translational (move forward)
- Vibrational (vibrate each other)
- Rotational (rotate around a central axis)
The kinetic energy of molecules differs directly with the absolute temperature. That is why gas phase is favored when temperature is high or even low. While in condensed phases such as solid and liquid, are favored by high pressure and low temperature. Always remember that high pressure put up molecules closer to each other that makes molecular
Compressibility of the Three Phases
We all know that solid and liquid is incompressible but gases have higher compressibility. Liquids incompressibility is known to be the foundation of hydraulic engineering. This field uses fluids to transfer forces that lift and move objects that are heavy.
The same with a jeepney driver who steps on the brakes, the incompressibility of the brake fluid allows the driver to transfer the pressure from his feet through the tubes to the brake shoes of the jeepney wheels. The brake shoes are pushed against the wheels that make the jeepney acceleration stops. However, if air gets into the brake lines, an accident may happen because pressure is exerted to the brake that compresses the air causing the jeepney not to stop.
States of Matter
Continuity of Phases
Temperature and pressure determine the phase of matter. For example, water can be solid ice as “ice cubes”, liquid water in mineral “mineral water” and vapor that depends on temperature and pressure. An alteration of pressure and temperature or both can cause a change in phase from solid to liquid to gas or vice versa.
- At a pressure of 760 torr at sea transformation, water freezes into ice at 0ᵒC and boils into steam at 100ᵒC
The transformation of phases just like in the water does not change its identity. It remains the same compound with a similar mass ratio of hydrogen. These transformations never change the substance identity it will always be retained.
Phase transformation can be observed using a molecular model of matter. A cooled gas will deplete in volume in order for the force of attraction between the molecules will be greater than their kinetic energy. The vapor condenses to a liquid when the forces of attraction between molecules are strong enough. Kinetic energy decreases when liquid is cooled that causes the particles to become rigid/solid.
Vapor – refers to the gaseous phase of a substance which is normally liquid or solid at room temperature.
Water vapor – refers to gaseous phase of water, liquid at room temperature
Volatile – liquids that can easily evaporate. Some of these liquids are alcohol, ammonia and ether
Condensation – the process of reduction of matter into a denser form, as in the liquefaction of vapor or steam meaning, the transformation of gas to liquid.
Evaporation – is the gradual alteration of state from liquid to gas that occurs at a liquid’s surface. This often takes place when liquid is heated.
Solidification – the process when liquid become compact and firm and turns into solid state.
Melting – the process where solid state liquids turns to liquid form again.
Deposition – the process where gas turns to solid without passing to liquid state.
Sublimation – the process where some solid materials become gas without passing to liquid state. Some examples of these are mothballs and deodorizers.
References; Science and Technology III by SEDP Series, Encarta